From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-io0-x233.google.com ([2607:f8b0:4001:c06::233]) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1eYlyZ-0001mz-CF for kexec@lists.infradead.org; Tue, 09 Jan 2018 04:57:29 +0000 Received: by mail-io0-x233.google.com with SMTP id f6so17110815ioh.8 for ; Mon, 08 Jan 2018 20:57:16 -0800 (PST) Date: Tue, 9 Jan 2018 14:02:18 +0900 From: AKASHI Takahiro Subject: Re: arm64 crashkernel fails to boot on acpi-only machines due to ACPI regions being no longer mapped as NOMAP Message-ID: <20180109050216.GB18820@linaro.org> References: <20171221103440.GJ28046@linaro.org> <20171222083308.cy3vwlyhig22q5ee@fireball> <20171225032500.GA8877@linaro.org> <20171226013217.GA2119@dhcp-128-65.nay.redhat.com> <20171226013517.GA2186@dhcp-128-65.nay.redhat.com> <20171226022807.GB8877@linaro.org> <20171226065636.GA5354@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20171226065636.GA5354@dhcp-128-65.nay.redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Dave Young Cc: Mark Rutland , "linux-efi@vger.kernel.org" , Ard Biesheuvel , Matt Fleming , Bhupesh Sharma , kexec@lists.infradead.org, James Morse , Bhupesh SHARMA , "linux-arm-kernel@lists.infradead.org" On Tue, Dec 26, 2017 at 02:56:36PM +0800, Dave Young wrote: > On 12/26/17 at 11:28am, AKASHI Takahiro wrote: > > On Tue, Dec 26, 2017 at 09:35:17AM +0800, Dave Young wrote: > > > [snip] > > > > > > Well, we may be able to change pr_warn() to pr_warn_once() here, but > > > > > > I hope that adding "numa=off" to kernel command line should also work. > > > > > > > > > > Hmm, adding "numa=off" to crashkernel bootargs works, and TBH it was > > > > > my initial thought process as well, but I am not sure if this will > > > > > cause any regressions on aarch64 systems which use crashdump feature. > > > > > > > > It should be fine since we use numa=off by default for all other arches > > > > ie. x86, ppc64 and s390. Actually disabling numa in kdump kernel can save > > > > mm component memory usage. > > > > > > > > > > Forgot to say I means in RHEL and Fedora we use numa=off for kdump.. > > > > Thank you for the clarification. > > (It might be better to make numa off automatically if maxcpus == 0 (and 1?).) > > Hmm, I did a quick test with qemu/kvm, kdump kernel boot without numa=off > I'm not sure why I do not see the warning messages on x86 > machines, maybe something arm64 specific? I didn't see the messages(i.e. "potential offnode page_structs") on arm64 qemu (with -smp 2 -numa node -numa node). It seems that qemu doesn't generate acpi slit(inter-node distance table). Thanks, -Takahiro AKASHI > > > > -Takahiro AKASHI _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec